Loss of Control in Flight · NTSB DEN08FA058

Piper PA-23-250 — Sterling, KS

1 fatal High-time pilot
DateFebruary 13, 2008
LocationSterling, KS
AircraftPiper PA-23-250
Purpose of flightPositioning
ConditionsDay · Visual Meteorological Cond
Phase / occurrenceEnroute-cruise Loss of control in flight
Pilot age27
Pilot total time3,050 hrs · High time
Time in type1,320 hrs
Fatalities1

Probable cause

The loss of pitch control during cruise flight resulting from the separation of the stabilator trim actuator due to inadequate maintenenace.

NTSB findings

  • Aircraft-Aircraft systems-Flight control system-Stabilizer control system-Failure
  • Aircraft-Aircraft oper/perf/capability-Performance/control parameters-Pitch control-Attain/maintain not possible - C
  • Aircraft-Aircraft handling/service-Maintenance/inspections-(general)-Inadequate inspection - C

What happened

The airplane was in cruise flight at 6,000 feet mean sea level when it entered an uncontrolled descent and impacted terrain in a right wing low attitude. The airplane cartwheeled, impacted a cow, and scattered components and debris over a distance of 668 feet. Examination of both stabilators revealed extensive aft streaking, initiating along the forward rivet line, consistent with working or "smoking" rivets. Examination of the stabilator trim tab fittings exhibited little deformation and the inboard rivet faces had been knocked off. The stabilator trim pushrod was not attached. The securing nut and cotter pin, used to secure the pushrod to the tab was missing. The lack of deformation to the trim pushrod is indicative that the securing nut backed out during flight. The stabilator trim bellcrank, left side, was loose within its attach point and exhibited significant freeplay. Disassembly revealed elongation of the attach hole. These observations indicate prolonged inadequate maintenance. A review of the pilot's training, experience, and qualifications revealed no issues.

An editorial "what led to it / how to avoid it" analysis for this accident is generated separately and will appear here.

View the official NTSB docket →